The tree-level diagrams relevant to the aforementioned \(2\rightarrow 2\)  matrix element are shown in Fig. REF ; details can be found in [1]}, [2]}, [3]}, [4]}, [5]}. The general strategy employed in this paper follows that of the unstabilized case. Briefly, the total matrix element \(\mathcal {M}\)  involves a contact diagram \((\mathcal {M}_{c})\)  as well as infinite sums over the diagrams (\(\mathcal {M}_{j,X}\) , \(\mathcal {M}_{(i),X}\) ) describing \(X = s\) , \(t\) , and \(u\) -channel exchanges of intermediate spin-2 states and spin-0 states:
\(\mathcal {M} = \mathcal {M}_{c} + \sum _{X \in \lbrace s,t,u\rbrace } \bigg [ \sum _{j=0}^{+\infty } \mathcal {M}_{j,X} + \sum _{i=0}^{+\infty } \mathcal {M}_{(i),X }\bigg ]\) 
